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Effect of SNPs in the BCMO1 Enzyme (BETASNP2)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT02276014
Recruitment Status : Completed
First Posted : October 27, 2014
Last Update Posted : October 6, 2015
Newcastle University
DSM Nutritional Products, Inc.
Information provided by (Responsible Party):
Newcastle-upon-Tyne Hospitals NHS Trust

Brief Summary:


Chronic intake of foods low in vitamin A (retinol) and provitamin A forming an unbalanced diet with little variety is common in young individuals in the United Kingdom (UK) population and can lead to subclinical micronutrient deficiency. Provitamin A sources such as β-carotene are cleaved centrally by the β-carotene 15,15'-monooxygenase (BCMO1) into retinal, the precursor of retinol. However, the amount of β-carotene and retinol produced after ingestion of β-carotene is highly variable between healthy individuals, with approximately 40% of the subjects being classified as low responders. Several stable isotope studies have shown a large disparity between the most efficient converters and the most inefficient converters of β-carotene with variations of up to 8-fold. It is possible that differences in β-carotene response may be due to single nucleotide polymorphisms (SNPs) in genes involved in aspects of β-carotene conversion. Previous work has shown that carriers of both, the 379V and 267S+379V BCMO1 variant alleles had a reduced ability to convert β-carotene. More importantly, 44% of the western population have the 379V haplotype. A high percentage of the Western population may therefore not be able to achieve adequate vitamin A intake if dietary β-carotene is a major source of their vitamin A intake. This is of particular relevance to vegetarians, to young individuals aged 19-24 years who have lower intakes of preformed retinol than any other age group, and to pregnant women. The aim of this study is to establish whether the maximum recommended dose for β-carotene of 7mg/day by the British Expert Committee on Vitamins and Minerals (EVM) can overcome the SNP effect in the BCMO1 enzyme.


The investigators hypothesize that the current maximum recommended intake of 7 mg of β-carotene per day cannot overcome the low convertor phenotype in BCMO1 to fulfill vitamin A requirements in these people.

Condition or disease Intervention/treatment Phase
Beta-carotene Bioavailability Vitamin A Deficiency Dietary Supplement: Beta-carotene Not Applicable

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 85 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single (Participant)
Primary Purpose: Basic Science
Official Title: Effect of SNPs in the Beta-carotene 15, 15'-Monooxygenase (BCMO1) Enzyme on Retinol Formation and Beta-carotene Plasma Responses
Study Start Date : April 2012
Actual Primary Completion Date : September 2014
Actual Study Completion Date : September 2014

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Vitamin A

Arm Intervention/treatment
Supplement A
Beta-carotene 7mg formulation A
Dietary Supplement: Beta-carotene
Supplement B
Beta-carotene 7mg formulation B
Dietary Supplement: Beta-carotene
Supplement C
Beta-carotene 7mg formulation C
Dietary Supplement: Beta-carotene

Primary Outcome Measures :
  1. Area under the plasma concentration versus time curve (AUC) of beta-carotene [ Time Frame: Pharmacokinetic measures (0,1,4,36,46,57,60 days post-dose) ]
  2. Area under the plasma concentration versus time curve (AUC) of [13C]retinol [ Time Frame: Pharmacokinetic measures (0,1,2,3,4,8,10,22,36,46,57,58,59,60,64,66,78,92,113 days post-dose) ]

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 45 Years   (Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Healthy individual.
  • Female.
  • Between 18 and 45 years of age.
  • Caucasian.
  • BMI between 18 and 30 kg/m2.
  • Subject willing and able to give written informed consent.

Exclusion Criteria:

  • Smoking.
  • Diabetes.
  • Gastrointestinal diseases.
  • Renal and hepatic diseases.
  • Hyperlipidaemia.
  • Preformed dietary retinol intake above 60% of reference nutrient intake (RNI) values.
  • Recreational drug use.
  • Multi-vitamin consumption.
  • Pregnancy.
  • Menopause.
  • Allergy or sensitivity to study products or ingredients.
  • Blood donation 3 months prior to screening.
  • Participation in other clinical study 4 weeks prior to study start.
  • Suspected inability or unwillingness to comply with study procedures.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT02276014

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United Kingdom
Newcastle NIHR Clinical Research Facility, Royal Victoria Infirmary
Newcastle upon Tyne, Tyne & Wear, United Kingdom, NE1 4LP
Sponsors and Collaborators
Newcastle-upon-Tyne Hospitals NHS Trust
Newcastle University
DSM Nutritional Products, Inc.
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Principal Investigator: Georg Lietz, PhD Newcastle University
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Responsible Party: Newcastle-upon-Tyne Hospitals NHS Trust Identifier: NCT02276014    
Other Study ID Numbers: 2011-01-18-BETASNP2
REC 11/NE/0211 ( Other Identifier: National Research Ethics Service (NRES) )
First Posted: October 27, 2014    Key Record Dates
Last Update Posted: October 6, 2015
Last Verified: October 2015
Keywords provided by Newcastle-upon-Tyne Hospitals NHS Trust:
Beta carotene
Additional relevant MeSH terms:
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Night Blindness
Vitamin A Deficiency
Deficiency Diseases
Nutrition Disorders
Vision Disorders
Eye Diseases
Beta Carotene
Molecular Mechanisms of Pharmacological Action
Protective Agents
Physiological Effects of Drugs
Growth Substances